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Jan. 9, 1962 H. E. TUCKER Re 25,110

DRAFT GEAR FOR RAILWAY CARS Original FiledSept. '7, 195] 2 Sheets-Sheet 2 QQ-Z WMV

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United States Patent V4Oce Re. 25,110 Reissued Jan. 9, 1962 25,110 DRAFT GEARS FOR RAILWAY CARS Herbert E. Tucker, Chicago, Ill., assignor to Cardwell Westinghouse Company, a corporation of Delaware Original No. 2,738,078, dated Mar. 13, 1956, Ser. No.

245,573, Sept. 7, 1951. Application for reissue Dec.

23, 1957, Ser. No. 704,848

8 Claims. (Cl. 213-45) Matter enclosed in heavybrackets appears in the original patent but forms no part of this reissue specilication; matter printed in italics indicates the addition made by reissue. f

This invention relates to draft gears for railway cars, and has for its principal object to provide a relatively soft cushioning unit of short travel and low capacity acting in buff and in draft, and a relatively hard long travel cushioning unit of high capacity also acting in bui only and in series with the relatively soft cushioning unit.

Other objects and advantages of the invention will appear as the description is read in connection with the accompanying drawings, in which:

FIG. l is a horizontal section through the draft gear and associated parts;

FIGS. 2 and 3 are cross-sections on the lines 2 2 and 3 3 of FIG. 1 respectively;

FIG, 4 is a diagram giving comparative curves of the two cushioning units and a combination of the two; and

FIG. 5 is a perspective view indicating how the resilient elements or spring elements are made up.

In the drawings, and 11 indicate spaced sills equipped with draft lugs 12 and 13 which together define a conventional draft gear pocket. Associated with those parts is a coupler shank 14 and a draft yoke 15 connected to the coupler shank in any suitable way.

The draft gear includes a housing 16 divided by a partition 17 into a generally rectangular rear chamber 18 (FIG. 2) for the low capacity cushioning unit, and a generally hexagonal front chamber 19 (FIG. 3) for the high capacity cushioning unit. v

The soft, low capacity or rear cushioning unit is made up of resilient elements or spring elements, generally indicated by 20, alternating with spacers. As shown in FIG. 5, each element is made up of a plate 21 of relatively incompressible material (preferably steel W16" S.A.E. 1010 is satisfactory) provided with rows of aligned, spaced openings 22, rubber'bars or mats 23 overlying the rows of openings on each side of the plate are connected by plugs 24; The bars and plugs are of mate` rial such as rubber composition, of suitable durometer hardness, for example 58 to 62. The connection between the bars and the plugs, or one bar and the plugs, is effected by vulcanizing, which may, or may not, also make the bars fast to the steel plates.

lIn making up the soft, low capacity cushioning unit in this embodiment, three resilient or rubber elements, including plates 21 and rubber blocks 23, alternate with steel spacer plates 25, the group or pack having an overall length in excess of the length of the chamber 18 approximately one inch, thus providing a one-inch soft travel low capacity cushion for buff and draft shocks. In use, it is assembled between the partition 17 and a back follower plate 26.

The high capacity long travel cushioning unit or front unit is preferably substantially as disclosed in the patent to Cardwell, 2,496,442 of February 7, 1950. However, in this instance the inner and outer coil springs are shown replaced by a cushioning element composed of tive main rubber springs, generally indicated by 27 in FIG. 1, a1' ternating with spacers 28. Each rubber spring is made up of a plate 32 provided on each side with concentric rubber rings 29 connected by blocks 30 through openings 31 formed in the plate 32.

The remainder of the friction draft gear disclosed in the said Cardwell patent is not here described in detail, but the disclosure in that patent is included by reference in the interest of brevity. Y

The rear follower y216 has a hollow boss 33 which receives the headed .end 42 of the bolt 40 which passes through the friction draft gear and serves to retain the units in assembled relation, as shown in FIG. l.

A front follower 37 is disposed between the coupler shank 14 and the friction cushioning unit and transmits buff loads therebetween. The front follower is limited in its forward travel by abutment with the front draft lugs 13. y

In operation, the soft low'capacity rubber cushioning unit provides one inch travel in all important draft shocks. The action is soft and easy and has plenty of capacity and travel. y

That soft low capacity cushioning unit also provides one inch travel on the rubber in buff. VAny light buing shocks will probably be taken care of mostly by the rubber, though undoubtedly as it reaches the end of its compression the friction will come in play. The two cushioning units acting together provide full three inches of travel in buff, and while light buff shocks are taken principally by the soft low capacity unit there is necessarily a blending, and as the low capacity unit reaches the capacity of limited travel the friction draft gear comes into full play for two inches, or approximately two inches, of capacity.

Generally speaking, the high capacity cushioning unit will be idle until there is a bul shock approaching the capacity or exceeding the capacity of the soft, low cushioning unit. When that occurs, the friction of the high capacity unit will come into play and take care i of the shock.

with inches of travel as abscissa and loads as ordinates.

The characteristic curve of the low capacity cushioning unit indicated at 51 is quite a long curve. The combination of the two is indicated by the curve 52 from which it will appear that the draft gear is softer than friction draft gears when considered as a whole, but has the softness of a rubber draft gear for draft shocks or bud shocks within the capacity of the lowsoft cushioning unit.

Wherever inthe specification and claims the terms hard and soft are employed to describe the cushioning units they should be understood to refer to the cushioning units as a whole and not necessarily to the individual elements thereof. The characteristic load-deflection curve for a relatively hard cushioning unit, of course, shows that for a given increment of load there results only a small deection, whereas `the characteristic load-deflection curve for a relatively soft cushioning unit for a similar increment of load would produce a 'substantially greater deflection.

` I claim:

l. In a draft gear for a railway car having a draft gear pocket, a draft yoke, followers movable by the yoke, and spaced stops against which the followers normally rest, a housing mounted in the draft pocket for longitudinal movement therein between one of said stops and one of said followers, said housing normally occupying a position with one end thereof abutting said one stop `and the opposite end thereof spaced from said one follower, a partition wall in said housing dividing it into two chambers, a cushioning unit in one of said chambers between said partition wall and said one follower, said cushioning unit including a series of rubber blocks alternating with relatively incompressible plates, a friction cushioning unit in the other of said chambers between said partition wall and the other of said followers, said onel follower being movable by said draft yoke away from its associated stop to cause said first mentioned4 cushioning unit to act in draft, said housing, during such movement of said one follower, being held against movement by the stop which it normally abuts, whereby said friction cushioning unit is prevented from acting in draft, said other follower being movable by said draft yoke away from its associated stop to cause both of said cushioning units to cooperatively act in buff.

2. In a draft gear `for a railway car having a draft gear pocket., a draft yoke, followers movable by the yoke, spaced stops against which the followers normally rest, a housing* mounted in the draft pocket for long i-A tudinal movement therein between one of said stops and one of said followers, said housing normally occupying a position with one endv thereof abutting said one stop and the opposite end thereof spaced from said one follower., a Partition, wall in Said housing dividing it intov two chambers of different lengths and cross-sections, a short travel cushioning unit in the shorter chamber between saidl partition wall and said one follower, said cushioning' unit including a series of rubber blocks alternating with relatively incompressible plates, -a friction cushioning unit in the second chamber between said partition wall and the. other of said followers, said short travel cushioning unit being softer than said friction cushioning unit, said one follower being :movable by said draft yoke away from its associated stop to cause said first mentioned cushioning unit to act in-draft, said housing,` during such movement of said onel follower, be ing held against movement by the stop which it normally abuts, whereby said friction cushioning unit is prevented from acting in draft, said other follower b eing'movable. by Said draft yoke away from .its associated. Stop t0. canse bot-l1 nf .Said cushioning units. to. @operatively ant, in bntf.

3- In a draft gear;- forv mounting in a draft gear pocket. of a railway car, said pocket having front and rear .Stop lugs, and adapted in be, antnatnd by a coupler yoke. encircling die gear, a. housing :rnnunted in the. pocket for longitudinal movement. therein. a partition wall. in Said, housing dividing it into. twov Chambers. f: different. lengths, a .rear cushioning unit in the chamber of shorter lengthl and having one Vend abutting said partition wall, a rear. follower abutting the opposite end of said cushioning unit, said reary follower and housing having cooperating portions for limiting relative movement of said follower toward said partition wall, and said portions being in longitudinally spaced relation. whereby saidI follower may move toward said partition wall to cause said cushioning unit to act in draft, a front cushioning unit in the chambers of greater length and having one end thereof abut-A ting said partition wall, a Ifront follower abutting the op. posite end of said front cushioning unit, said front fol. lower and said housing being movable toward said rear follower to cause both of said cushioning units to act in buff, said housing normally abutting against said front stops to prevent movement thereof when the gear is acting in draft whereby said front cushioning unit is prevented from acting in draft.

4. The invention recited in claim 3, wherein said rear cushioning unit is softer than said front cushioning unit.

5. In a draft gear for mounting in a draft gear pocket of -a railway car, said pocket having fro-nt and rear stop lugs, and adapted to be actuated by a coupler yoke encircling the gear,'a housing mounted in the pocket for longitudinal movement therein, a partition wall in said housing dividing it into front and rear chambers, a rear cushioning unit in said rear chamber having one end thereof abuttingvsaid partition wall, a rear follower abutting the opposite end of said cushioning unit, said follower and housing having cooperating portions for limiting relative movement. of said rear follower toward .said

partition wall and said portions normally being in longitudinally spaced relation whereby said follower may move toward said partition wall to cause said rear cushioning unit to act in draft, a front cushioning unit in said front chamber `having one end `abutting said partition wall, and a front follower abutting the opposite end of said front cushioning unit, said `front follower and said housing being movable toward said rear follower to cause both of said cushioning units to act in buff, said housing normal-ly 'abutting against said front stops to prevent movement thereof when the gear is, acting in draft whereby said front cushioning unit is prevented from acting in draft.

6. A selective travel draft geur arrangement for use with coupler-yoke means, in d railway car zmderfmme that has a draft gear pocket, said underframe having front and rear stop means at opposite ends of said pocket and in which the draft gear arrangement provides greater cushioned travel in buff than in draft, the combination yof d draft gearcasing mounted in said pocket dnd have ing an open from end, cushioning mechanism in the casing including friction-producing elements projecting through said open end of the casing, front and rear follower means positioned at opposite ends of the casing engugcqble with said coupler-yoke means und said stop means, means including said cushioning mechanism biasing one endV of the casing against one of said stop means when the geur is in its release position and with the casing being of such length with respect 10i the pocket and said follower means that the casing is capable of movement within said pocket limited to an amount equal 11oL he desired maximum draft travel, said casing adjacent the open end thereof having longitudinally spaced shouldgrs, the forward or outermost one of which is adapted to react against `said front stop means, and the innermost one being adapted to engage, said front follower means, said from follower means having a. cross-sectional shape c ompalible lo that. of the open end of the casing whereby itmay lmove into said open end af the casing inV flank:- ing relationship, to. said outermost shoulders and against scid innermost shoulders, whereby on draft .said outermost shoulders limit forward travel 0f said coupler-yoke` means, und on buyj said innermost shoulders limit reap. werd; travel Qf .Said coupler-yoke means.

7. A selective travel draft gear arrangement for use wil-hv coupler-yoke meurs? in ay railway cur underfrume that; has a draftv gear pocket having front and rear stop means atv opposite ends 0f the pocket und in which the draft gear arrangement provides greater cushioned travel; in buff than in draft; in combination, compression members` providing u casing having an open end und front and rear follower means for opposite ends of the casing, said casing having the open end thereof formed to provde outwardly directed, longitudinally spaced outer and inner sets of shoulders, the :follower means for the open end of said casing having 'a cross-Sectional shape con-V forming IQ the arrangement of the inner set of shoulders to u ccammmluzev longitudinal movement thereof through the space between the shoulders of said outer set for engagement against the shoulders of said inner' set and being 0f less dimension lengthwise than the lengthwise spacing between said outer and inner set-s of shoulders, with the other of said follower means overlapping the other endV of said casing for solid abutment therewith in` limiting buffc travel' of said coupler-yoke means, said frontr follower means having a central portion engageuble with said coupler-yoke means and edge portions engageuble with said front stop means and said rear follower means having a central portion engageable with said coupler-yoke means and having edge portions engageable with said rear stop means, and cushioning mechanism. in Suid casing reacting between said front and rear fol.- lower means and including friction-producing elements engageable internally with said casing and. projecting through the open end thereof for engagement with thefollower means thereadjacem, said casing being of such,-

length with respect to said pocket and said front and rear follower means that the casing is capable of movement in s..id pocket to an amount corresponding to the maximum draft travel of said arrangement, with the portion of said casing between said inner set of shoulders and scid other end thereof being stressed in compression by engagement between said front and rear follower means in limiting but movement of said coupler-yoke means, and with the portion of said casing between said outer set of shoulders thereof and said other end thereof being stressed in compression by reaction between the front stop means and the coupler-yoke means in limiting draft movement of said coupler-yoke means to an amount less than the permissible bu movement thereof.

8. In a draft gear for mounting in a draft gear pocket of a railway car, said pocket having front and rear stop lugs, and adapted to be actuated by a coupler yoke etlcircling the gear, a housing mounted in the pocket for longitudinal movement therein and having a xed internal partition wall dividing the housing into front and rear chambers, a rear cushioning unit in said rear chamber and having one end thereof abutting said partition wall, a rear follower disposed between the other end of said rear cushioning unit and the rear stop lugs and movable forwardly with said yoke to compress said rear cushioning unit in draft, said rear follower normally abutting said rear stop lugs and said rear cushioning unit reacting against said rear stop lugs through said rear follower to normally bias said housing forwardly against said stop lugs for preventing movement thereof when the gear is acting in draft, a front cushioning unit in said front chamber having one end abutting said partition wall and front follower means interposed between said coupler and the opposite end of said front cushioning unit for movement rearwardly towards said partition wall in response to rearward movement of the coupler to cause both of said cushioning units to act in buff.

References Cited in the le of this patent or the origlnal patent UNITED STATES PATENTS 

